class Elevator:
DIRECTION_UP = 1
DIRECTION_DOWN = -1
DIRECTION_STAND = 0
LEAVE_DOORS_OPEN = 2
def __init__(self):
self.driver = Driver()
self.previous_floor = 1
self.direction = self.DIRECTION_UP
self.queue = [] # A Queue of orders
self.task = [] # The current order that is being taken care of
self.motor_speed = 1000
self.elevator = None # *** hva brukes denne til og hvor settes den til en verdi? ***
def go_to_floor(self, floor, lock):
"""does what its name implies"""
current_floor = self.driver.getCurrentFloor()
if not current_floor:
current_floor = self.previous_floor
if current_floor < floor:
self.direction = self.DIRECTION_UP
self.driver.move(OUTPUT.MOTOR_UP, self.motor_speed)
elif current_floor == floor:
self.driver.stop()
self.pop_task(lock)
elif current_floor > floor:
self.driver.move(OUTPUT.MOTOR_DOWN, self.motor_speed)
self.direction = self.DIRECTION_DOWN
def pop_task(self, lock):
"""removes a task from the list of tasks and preforms cleanup"""
lock.acquire()
floor = self.task.pop()
lock.release()
light = self.driver.getAccordingLight(INPUT.IN_BUTTONS, floor)
self.driver.setChannel(light, 0)
self.open_doors()
def open_doors(self):
"""simulates opening the doors of the elevator and waiting"""
start = time.clock()
while time.clock() < self.LEAVE_DOORS_OPEN + start:
self.driver.stop()
def add_job(self, floor, direction, lock):
"""adds a job to the queue or task"""
if task:
# check whether this could be added as a subtask
if (
self.direction == self.DIRECTION_UP == direction
and self.previous_floor < floor <= self.task[len(self.task) - 1][0]
):
self.add_subtask(floor, direction, lock)
elif (
self.direction == self.DIRECTION_DOWN == direction
and self.previous_floor > floor >= self.task[len(self.task) - 1][0]
):
self.add_subtask(floor, direction, lock)
else:
lock.acquire()
self.queue.append((floor, direction))
lock.release()
else:
lock.acquire()
task.append((floor, direction))
lock.release()
def add_subtask(self, floor, direction, lock):
"""adds a subtask to the task in correct order"""
lock.acquire()
for i, sub in enumerate(self.task):
if direction == self.DIRECTION_DOWN:
if sub >= self.task[i]:
self.task.insert(sub, i)
else:
if sub <= self.task[i]:
self.task.insert(sub, i)
lock.release()
def read_inputs(self, lock):
"""reads inputs and processes them"""
for sig in INPUT.BUTTONS:
if self.driver.readChannel(sig):
(floor, type) = self.driver.channelToFloor(sig)
light = self.driver.getAccordingLight(type, floor)
self.driver.setChannel(light, 1)
if type == INPUT.IN_BUTTONS:
self.add_subtask(floor, self.direction, lock)
elif type == INPUT.DOWN_BUTTONS:
job = (floor, self.DIRECTION_DOWN)
if self.check_job(job):
self.add_job(floor, self.DIRECTION_DOWN, lock)
else:
ElevatorProcess(target=self.elevator.send_job, args=(self.elevator, job)).start()
elif type == INPUT.UP_BUTTONS:
job = (floor, self.DIRECTION_UP)
if self.check_job(job):
self.add_job(floor, self.DIRECTION_UP, lock)
else:
ElevatorProcess(target=self.elevator.send_job, args=(self.elevator, job)).start()
if self.driver.readChannel(INPUT.OBSTRUCTION):
self.driver.stop()
floor = self.driver.getCurrentFloor()
if floor:
self.driver.setFloorIndicator(floor)
self.previous_floor = floor
def check_job(self, job):
"""checks whether or not this elevator wants the given job"""
(floor, direction) = job
if not task:
return True
elif (
self.direction == self.DIRECTION_UP == direction
and self.previous_floor < floor <= self.task[len(self.task) - 1][0]
):
return True
elif (
self.direction == self.DIRECTION_DOWN == direction
and self.previous_floor > floor >= self.task[len(self.task) - 1][0]
):
return True
else:
return False
def reset_lights(self):
for l in OUTPUT.LIGHTS:
self.driver.setChannel(l, 0)
def pick_from_queue(self):
"""picks the next suitable job from the queue"""
counter = 0
while True:
for i in len(self.queue):
if abs(self.queue[i][0] - counter) <= counter:
self.task.append(self.queue[i])
self.queue.remove(self.queue[i])
return
counter += 1
def start(self, handler):
"""starts the elevator"""
self.handler = handler
lock = Lock()
input_reader = ElevatorProcess(target=read_inputs, args=(self, lock))
input_reader.start()
while True:
if self.task:
self.go_to_floor(self.task[0][0], lock)
elif self.queue:
lock.acquire()
self.pick_from_queue()
lock.release()
input_reader.terminate()
